The Digital Capacitive Touch Sensor TTP223B module Switch is based on a touch-sensing IC (TTP223B) capacitive touch switch module. Allows you to remove the worry of conventional push-type keys. Digital Capacitive Touch Switch Module is based on TTP223B. Normally, it outputs low and keeps at low power state. When a touch is sensed on the circular marked region, it outputs high and switches to the quick response state. When not being touched for 12 seconds, it switches to low power state again.